I've been working on a problem and I'm stumped :| I'm usually pretty good at deriving the equations for problems and solving them once I find out what I need to be solved. But this one is a bit too ambiguous for me, and I'm looking for a few hints :) Anything is appreciated! On an essentially friction-less, horizontal ice rink, a skater moving at 3.0m/s encounters a rough patch that reduces her speed by 45% due to a friction force that is 25% of her weight. Use the work-energy theorem to find the length of this rough patch. I've tried a few methods but, alas, no answer. The back of the book says 1.5m if that is of any assistance. Thanks again!